The first hammocks were woven from the bark of the tree Hamak. The Sisal (looks similar to aloe vera) later replaced the bark as the material. Sisal was unavailable and was especially soft sisal. Only about 60 years ago sisal was replaced by cotton. Sisal is often rumored that it was the better material against mosquitoes, but this was never confirmed. However, cotton is softer and does not scratch, so this is now the material of choice. With cheap hammocks nylon is now used, this material is often too hard and restricts the comfort. On trade route between India, Central and South America, the hammock came to Asia. Over the years, so the hammock was always evolving. Created new types of hammocks such as the famous Brazilian Hammocks.